Reverse cycle heating and cooling system



May 29, 1945. s. .1. BENN 2,376,859

REVERSE CYCLE HEATING AND COOLING SYSTEM Filed Dec. 29, 1943 2 Sheets-Sheet l gym/MM THE-.1...

May 29, 1945. 5. J. BENN REVERSE CYCLE HEATING AND COOLING SYSTEM Filed Dec. 29, 1945 2 Sheets-Sheet 2 Emma;

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Patented May 29, 1945 I REVERSE CYLE HEATING AND COOLING SYSTEM Stephen J. Benn, Philadelphia, Pa.

Application December 29, 1943, Serial No. 516,085

8 Claims.

This invention relates to reverse cycle heating and cooling systems such as employ the compression refrigeration principle, for heating buildings or auditoriums in winter and for cooling the same during the hotter seasons of the year.

Systems of the class mentioned comprise generally an air conditioning chamber, air ducts connecting said chamber with the auditorium, a fan or blower for withdrawing air from the auditorium through one of said ducts and returning the same through the other duct; together with heating and cooling units in said conditioning chamber, and means for selectively utilizing said units as needed.

The object of this invention is to provide a comparatively simple system of the class stated, whereby a substantially uniform temperature may be maintained irrespective of variations in the outside temperature.

A further object is to provide means in a system of the character under consideration whereby the heating and cooling units may be selectively controlled by the variations in the outside temperature.

A further and particular object of this invention is to provide means increasing the efficiency of the system and thereby reducing the operating costs to a minimum.

The invention will be more readily understood by references to the accompanying drawings forming a part of this specification and in which:

Figure 1 is a diagrammatic sectional view of a portion of a building equipped with an air conditioning system embodying the invention, the connecting pipes and the electric controls being omitted to avoid undue confusion.

Figure2 is a schematic diagram of the general layout including a manual summer-winter selective control switch, and

Figure 3 is a detail diagram of the selective control portion arranged for automatic actuation.

Referring now to Figure 1 of the drawings, 55 indicate outer walls of a building and 6 a floor of the rooms or auditorium I to be serviced by the system. In another room of the building, such a basement 8, is located the main operative parts of the device. These comprise the condensers and evaporators, the compressor and motor for operating the same, and means for maintaining a circulation of air about the condensers and evaporators and to and from the auditorium. As systems of the kind under consideration are usually employed for heating and cooling rooms for public assembly, I have herein designated such room as an auditorium, although it is to be understood that the system may be used for heating and cooling the rooms of private dwellings, hotels, oifices or any other rooms or compartments. Also, I have designated the basement as to locus of the main operative elements of the system, as the basement is where they will usually be located, but it is obvious that any convenient room or space may be utilized for the purpose. Hence, the word auditorium as used herein should be construed to mean the place to be heated or cooled; and basement as the room or space wherein the operative parts are located.

Arranged in the basement is an air-conditioning chamber 9 connected at one end to a duct lllleading from the auditorium l, and at the opposite end to a duct II for returning the air to the auditorium. Located within the chamber 9 is a condenser I2, an evaporator I3, and a fan or blower I4 driven by a motor I5. Connected to the condenser and evaporator in a manner hereinafter described, is a compressor I6 operated by a motor I1, and having the usual receiver I8. When it is desired to heat the auditorium the compressor is connected to the condenser I2. The fan I4 will create a circulation of air from the auditorium, through the chamber 9 in contact with the heated condenser, and then return the reconditioned air to the auditorium through the return duct II. To cool the auditorium, the communication between the compressor and condenser is shut off and communication between the compressor and evaporator I3 established, thereby cooling the air as it passes through the ducts l0 and II and chamber 9. Arranged in the duct II] is a damper I9 for controlling the passage of air through the conditioning chamber as will be described more fully hereinafter.

To supply fresh air to the air passing to the auditorium, a duct 20 is provided which extends from a point in communication with the outside atmosphere to the chamber 9, discharging therein at the inlet end of said chamber to mingle with the air of the general circulating current and to pass therewith through the condenser I2 and evaporator I3. The amount of fresh air admitted may be controlled by a damper 2|.

In refrigerating systems of the type herein employed, each condenser must be in operativecommunication with an evaporator, and each evaporator communicate with a condenser. To

, this end an evaporator 22 is in communication with the condenser l2; and a condenser 23 with the evaporator l3. The connections betweenthe compressors and cooperating evaporators are not shown in Figure 1 as it would tend to confuse the figure; but these connections are fully illustrated in the diagrammatic Figure 2. This con-' denser 23 and evaporator'22 are arranged in an auxiliary chamber 24 through which a circulation of air is maintained by a fan or blower 25 driven by a motor 28 the air being drawn in from outside thebuilding and after passing through the chamber 24, dischargedv whenever desired, usually to the outside atmosphere, as by a discharge duct 21.

The portions of the device so far described are preferably .arranged in a unitary housing 28,-

insulated for both heat and noise'and divided into extends from the compressor l8 and is forked as at 43 forming branches 44 and 45 connected to the condensers l2 and 23 respectively. In the branch 44 is an electrically actuated valve 45. and a similar valve 41 is in-the branch 45. Re-

turn pipes 48 and 49 from the condensers merge at 58 into a single pipe 5l'discharging into the receiver 18.

Extending from the receiver is a pipe 52 have ing branches 53 and 54 extending to the evaporators 22 and I3 respectively, said branches having electrically actuated valves 55 and 59 respectively. Return pipes" and 58 lead from the evaporators and merge into a single return 59 to the compressor.

For summer use to cool the auditorium, th valves 41 and 55 are opened, and the valves 45 and 55 closed. The refrigerant is then forced bythe compressor through 42 and 45 into the condenser 23, then returned through 49 and 5| to the receiver l8. From the receiver it is conducted through 52 and 55 to the evaporator l3, and returned through 58 and 59 to the com- 29 for the compressor, etc. Although this arrangement is preferable, it will be obvious that it may be varied without departing from the invention.

As stated above, the air for the auxiliary chamber 24 is drawn in from the outside atmosphere, and to this end an inlet duct 35 is provided, leading into the compressor chamber 29, preferably at the end of the housing opposite to the chamber 24, so that the air will be heated by the compressor and motor on its passage to the chamber 24, and also serve to cool the compressor and motor. A duct 35 connects the chamber 24 with the adjacent end of the chamber 28. Located in the inlet duct 35 is a damper 31 to control the amount of outside air passing to the chamber 24; and it is preferable that this damper be automatically controlled by the temperature of the air being discharged from said chamber. To this end a thermostat 38 is arranged in the chamber 24 at the discharge end thereof, that is, between the condenser 23 and evaporator 22, and the receiving end of the discharge duct 21. This thermostatic control is connected to the damper 31 as diagrammatically indicated at 39. Extending from the return air duct ill to the end of the pressor. The air current through the air conditioning chamber 9 is thus cooled by the evaporator before being returned to the auditorium, and the rate of flow of the cooled air is controlled or regulated by the damper l9. By closing or partly closing the damper l9, and more or less opening the damper 2|, the desired quantity of fresh air may be injected into the circulating current.

Inwinter, the valves 58 and 41 are closed and the valves 45 and 55 opened. The refrigerant is then forced from the compressor through 42 and 44 to the condenser l2 and returned through 48 and 51 to the receiver I8: thence through 52 and 53 to the evaporator 22 and'ret'urned through is accomplished by sufficiently heating the air chamber adjacent the duct 35 is a bypass 48 which'is provided with a damper 4|. 5 The eillciency of the device depends largely upon-the temperature of the air in the chamber 24, as will be understood, In hot weather sum-1 cient air will usually be admitted through the duct 35; but in cold weather the temperature of the chamber 24 should be higher, and under such conditions the thermostat 38 will operate to more or less close the damper 31, causing the blower orfan 25 to draw air through the by-pass 48. This air being already warm is further heated by the compressor and motor, and by mingling with the now comparatively small amount of air entering through duct 35, assists in heating the same before entering the chamber 24.

In Figure 2 is illustrated the complete general layout including the cross connections between the condensers and evaporators, and with the connections between the same and the compressor, together with the selective valves arranged for changing from winter to summer operation and vice versa. As shown therein a conductor pipe 42 for the compressed refrigerant pa sing through the chamber 24. Part of the heat for this purpose is supplied by the otherwise waste heat from the compressor l5 and motor 11 which are located in the passageway of. the fresh air entering through the inlet duct 35. To regulate the entry of the cold outer air and maintainthe desiredtemperature in the chamber 24 for greater efliciency, the damper 31 is provided, and this is operated by the thermostat 38 in the discharge end of the chamber 24. Should the air entering 35 be too cold to be sumciently tempered by the waste heat of the compressor and motor, the damper 31 is accordingly closed and the necessary air for proper circulation through the chamber is drawn from the bypass 48. As this is warm 'air from the auditorium, it is evident that the thermostat 38 will maintain the temperature in control C by a manually actuated switch 55 and lines 66. This form of control is but semi-automatic, as the switch 65 must be manually operated to connect the seasonal thermostatic switch 63 or 64 to the control C. In order to render the system completely automatic, the summer and winter controls are selectively connected to actuate the switches by thermostatic means 61 havcirculating air from a room through said conditioner and return, a second chamber, an evaporator and a condenser in said chamber cooperatively connected to the first said condeneser and evaporator respectively, a compressor, means for selectively connecting either of said condensers and its respective evaporator to said compressor, means for directing a stream of air over said compressor and through said second chamber, a damper controlling said stream of air, and thermostatic means in said second chamber for actuating said damper.

2. In a system of the class described, an air conditioning chamber, a heating condenser and a cooling evaporator in said chamber, means for circulating air from a room through said conditioning chamber comprising a duct from said room to one end of said chamber and a duct from the opposite end of said chamber to said room and a blower in said chamber, a second chamber, an evaporator and a condenser in said second chamber cooperatively connected to the first said condenser and evaporator respectively, a compressor, means for selectively connecting either of said condensers and its respective evaporator to said compressor, means for directing a stream of air adjacent said compressor to receive heat therefrom and then through said second chamber, a damper controlling said stream of air, thermostatic means in said second chamber for actuating said damper, a bypass from the first said duct to discharge with said stream of air adjacent the compressor, and a damper in said bypass.

3. In a system of the class described, an air conditioning chamber, a heating condenser and a cooling evaporator in said chamber, means for circulating air from a room through said conditioning chamber comprising a duct from said room to one end of said chamber and a duct from the opposite end of said chamber to said room and a blower in said chamber, a second chamber, an evaporator and a condenser in said second chamber cooperatively connected to the first said condenser and evaporator respectively, a compressor, thermostatic means for selectively and automatically connecting either of said condensers and its respective evaporator to said compressor, means for directing a stream of air adjacent said compressor to receive heat therefrom and then through said second chamber, a damper controlling said stream of air, thermostatic means in said second chamber for actuating said damper, a bypass from the first said duct to discharge with said stream of air adjacent the compressor, and a damper in said bypass.

4. In a system of the class described, an air conditioning chamber having a receiving end and a discharge end, a heating condenser and a cooling evaporator in said chamber, means for circulating air from a room through said conditioning chamber comprising a duct from said room to the receiving end of said chamber, and a duct from the discharge end of said chamber to said room and a blower in said chamber, a second chamber, an evaporator and a condenser in said second chamber cooperatively connected to the first said condenser 'and evaporator respectively, a compressor, thermostatic means for selectively and automatically connecting either of said condensers and its respective evaporator to said compressor, means for directing a streamof air adjacent said compressor to receive heat therefrom and then through said second chamber, a, damper controlling said stream of air, thermostatic means in said second chamber for actuating said damper, a bypassfrom the first said duct to discharge into said stream of air adjacent the compressor, a damper vin said bypass, and a valve controlled fresh air duct opening into the receiving end of the conditioning chamber,

5. In a system of the class described an air conditioning unit comprising an insulating housing divided into a conditioning chamber having a receiving end and a discharge end, a second chamber and a compressor chamber, a heating condenser and a cooling evaporator in said conditioning chamber, an evaporator and a condenser in the second chamber, cross connected to the first said condenser and evaporator, an inlet air duct leading into the receiving end of the conditioning chamber and a discharge duct leading from the discharge end thereof, a damper on said inlet duct, a fresh air duct leading into the receiving end 'of the conditioning chamber, an air duct discharging into one end of the compressor chamber, a damper in the last said duct, a, duct connecting the opposite end of the compressor chamber and one end of the said second chamber, a discharge duct at the opposite end of the said second chamber, a thermostat in said second chamber adjacent the discharge duct, and operatively connected to th damper in the inlet duct to the compressor chamber, a valved bypass from the inlet duct of the conditioning chamber, and a receiver in said compressor chamber.

6. In a system of the class described, a heating condenser and a cooling evaporator, means for circulating the air from a room to be conditioned adjacent said condenser and evaporator and back to said room, a second evaporator and condenser, a compressor and a cooperating receiver, a pipe leading from said compressor,

- branches from said pipe to the first and second leading from said receiver, branches from the last said pipe to the first and second mentioned evaporators respectively, return pipes from the evaporators to said compressor, an electrically controlled valve in each of said last mentioned branches, and an automatic control for opening the valves to one of said condensers and to the cooperating evaporator and closing the valves to the other condenser and evaporator.

7. In a system of the class described, a heating condenser and a cooling evaporator, means for circulating the air from a room to be conditioned adjacent said condenser and evaporator and back to said room, a second evaporator and condenser, a compressor and a cooperating receiver, a pipe leading from said compressor, branches from said pipe to the first and second mentioned condensers respectively, an electrically controlled valve in each or said branches, return pipes from the condensers to the receiver, a pipe leading from said receiver, branches from the last said pipe to the first and second mentioned evaporators respectively, return pipes from the evaporators to said compressor. an electrically controlled valve in each of said branches, an automatic control for opening the valves to one of said condensers, and to the cooperating evaporator and' closing the valves to the other condenser and evaporator, and a selector switch for reversing the operation of the automatic valve control for winter or summer use.

8. In a system 01' the class described, a heating condenser and a cooling evaporator. means for circulating the air from a room to be conditioned adjacent said condenser and evapora- 3 tor and back to said room, a second evaporator and condenser, a compressor and a cooperating receiver, a pipe leading from said compressor. branches from said pipe to'the first and second mentioned condensers respectively, an el'ectri- .caiiy controlled valve in each or said branches,

tioned evaporators respectively,

return pipes from the condensers to the receiver, a pipe leading from said receiver, branches from the last said pipe to the first and second menretum pipes from the evaporators to said compressor, an eleccondenser and evaporator, means for reversing the operation of the automatic valve control for winter or summer use, and a thermostat exposed to the outside temperature for actuating said reversing means.

STEPHEN J. BENN. 

